Question

Complete the process of iron rusting by filling the blanks. Suggest a way to prohibit the process. The iron rust is formed due to reaction. Different regions on iron surface become anode and cathode.

Reaction on anode region:

Fe_(s) → Fe²⁺ _(aq) + 2e^-

Reaction on cathode region:

O2_(g) + 4H⁺ _(aq) +……… → 2H₂O_(I)

when Fe²⁺ ions migrate from anode region they react with……..to fomm Fe³⁺ ions.

A reddish coloured hytirated oxide is formed from……….ions. It is called rust.

2Fe³⁺ _(aq) + 4H₂O_(I) → +………+ 6H⁺ _(aq)

A way to prevent rusting………..

Answer 1

The iron rust is formed due to electrochemical reaction. Different regions on iron surface become unode and cathode.

Reaction on anode region:

Fe_(s) → Fe²⁺ _(aq) + 2e^-

Reaction on cathode region:

O2_(g) + 4H⁺ _(aq) + 4e^- → 2H₂O_(I)

when Fe²⁺ ions migrate from anode region they react with water to form Fe³⁺ ions.

A reddish coloured hydrated oxide is formed from Fe³⁺ ions. It is called rust.

2Fe³⁺ _(aq) + 4H₂O_(I) → + Fe₂O₃. H₂O_(s) + 6H⁺ _(aq)

A way to prevent rusting by colouring with acrylic paints, Zn plating, galvanizing, anodizing, alloying, etc.